Two-part electrical connectors



2 Sheets-Sheet 1 Filed Aug. 10, 1959 luv- g- 29, 1961 J. J. CHAMBERLAIN2,998,588

TWO-PART ELECTRICAL CONNECTORS Filed Aug. 10, 1959 2 Sheets-Sheet 2UNLOCKED 12km." UWWQIMW United States Patent 2,998,588 TWO-PARTELECTRICAL CONNECTORS John Joseph Chamberlain, Benington, England,assignor to The English Electric Company, Limited, London, England, aBritish company Filed Aug. 10, 1959, Ser. No. 832,774 6 Claims. (Cl.339-7 This invention relates to two-part electrical connectors.

The invention essentially consists in a twopart electrical connectorhaving at least one contact pin and cooperating resilient contactsleeve, and provided with a clamping member through an aperture in whichthe contact sleeve passes at least when the two parts of the connectorare in engagement, the walls of the aperture acting on movement of theclamping member from a released to a clamped position to deform thecontact sleeve to cause it to grip the contact pin.

Although the invention may be applied to connectors having only a singlepin and sleeve contact pair, it is more particularly applicable tomulti-point connectors, such as may be used for the interconnection ofelectronic or communication apparatus, in which it is desired to combineconsistently good electrical contact between the pins and the sleeveswith ease of separation and engagement of the two parts of theconnector. In such a construction the clamping member will of course becommon to all the contact pairs, each contact sleeve passing through aseparate aperture in the clamping member.

Other features of the invention will be evident in the followingdescription of various forms of electrical connectors embodyingpreferred forms of the invention. The description refers to theaccompanying drawings, in which:

FIG. 1 is a side elevation, partly sectioned, of a multipoint two-partconnector;

FIG. 2 is a transverse cross-section of the connector shown in FIG. 1 onthe line marked 2P-2 in that figure;

FIGS. 3a and 3b show respectively a plan and a crosssection of part of aclamping member included in the construction of FIG. 1;

FIG. 4 shows details of the mating contact parts of the connector;

FIG. 5 is an external view of the complete connector; and

FIG. 6 shows a cross-section through the mating contact parts of afiurther form of connector.

The general arrangement of the connector shown in FIGS. 1-5 of thedrawings will be evident from a consideration of FIGS. 1 and 2. The twoparts of the connector, which may be distinguished as the plug part 10and the socket part 11, each consist of a composite body member 12carrying the contact members, an outer casing formed by a cable sleeve13 for receiving the incoming cables to the connector, and a retainingring 14 by means of which the body 12- is clamped against an end face ofthe cable sleeve 13. The two parts of the connector are circular incross-section, the retaining ring 14 being screwed on to the cablesleeve 13. Threaded studs 15 pass throughthe retaining ring 14 and bearagainst the wall of the cable sleeve 13 to prevent relative rotation ofthese parts. Further threaded studs 16 prevent relative rotation of thebody member 12 and the retaining ring 14.

Each of the body members 12 comprises two discs 12a and 12b of mouldedinsulating material with a resilient sealing disc 17 compressed betweenthem. A series of holes, with their centres disposed on three circlesco-axial with the connector, are provided in these components for theplug contacts 18 or socket contacts 19 of the connector. Each hole inthe outer plate 12a of the body member is counterbored to provide alocation for a shoulder 20 formed on the contact. With thisconstruction, damaged contacts may be very easily replaced, while theseal 17 prevents the ingress of moisture to the interior of theconnector part through the apertures in the body members.

The body members 12 may, of course, be moulded each from a single pieceof insulating material, the contacts being permanently inserted withinthe body member during the moulding process.

The exposed parts of the plug contact members 18 form contact pins 21,and those of the socket contact members 19 form sleeve contacts 22;these parts will be described in more detail with reference to FIG. 4,it being sufii-cient here to mention that the contact pin 21 is a solidpin while the sleeve 22 is sufficiently thin to be resilient and readilydeformable.

A generally circular clamping plate 23 is pivotally secured to thesocket part 11 of the connector by means of a screw 24, both the plate23 and the screw 24 being moulded in insulating material. The clampingplate has formed in it a series of slots 25, one for each cooperatingcontact pair of the connector. The slots 25 are arcua-te in form, theirside walls being formed by I arcs of constant angular length havingtheir centres on the axis of the connector; one end of each slot isclosed by a semicircular portion having the same diameter as theseparation of the arcuate slot Walls, while the other end of the slot isclosed by a part-circular portion of rather greater diameter. This slotformation does not extend for the full depth of the clamping plate 23,the slots 25 being widened as shown at 26 where they open on to theinner face of the clamping plate 23 to provide a clearance for thecontacts. The formation of each of the slots 25 is shown in plan and incross-section in FIGS. 3a and 3b respectively.

Since, as will be clear from FIG. 2, the formation of the slots 25 inthe clamping plate repeats the formation of the connector contactmembers, movement of the clamping plate 23 about its central pivotthrough an angle of about 10 degrees will cause each contact sleeve 22to move from one end to the other of the associated slot 25. In thereleased position of the clamping plate 23, each sleeve contact 22 liesin the enlarged end portion 25a of its associated slot, the diameter ofthis end portion being such as to allow a slight clearance around thecontact sleeve and thus to permit the ready insertion or removal of theassociated contact pin 21. When the clamping plate 23 is moved to itsclamped position, the arcuate side walls of the narrower portion of theslot, which are separated by a distance slightly less than the normaldiameter of the contact sleeve 22, deform the cont act sleeve to causeit to grip the contact pin. Since the contact sleeves lie at the extremeend of the narrower portion of the slot 25, between parallel parts ofthe slot walls, when the clamping plate 23 has completed its movement toits clamped position, there is no tendency for the clamping plate toreturn of its own accord to its released position.

The locking action of the clamping plate 23 is assisted by the formationof the contact pins 21 and sleeves 22. An enlarged view of thesecomponents is shown in FIG. 4 of the drawings on a larger scale. Thecontact members are here shown side by side but in the same relativeposition as in their normal engaged position.

The contact pin 21 is a solid copper pin of circular cross-section,having -a tip portion 27 of constant diameter and a reverse-taperedportion 28 between the tip 27 and the pin root. The sleeve contact 22 isa thin-walled copper sleeve having a pair of diametrically opposed slots29 running longitudinally from its open end and terminating each in acircular hole 30. As will be seen from FIG. 4, the bottom of each cut29, formed by the hole 30, is situated when the contact pin and sleeveare in normal engagement at a point well down the constant diameter tipportion 27 of the contact pin. Comparison with FIG. 1 shows that theaction of the clamping plate 23 in deforming the contact sleeve 22consists in bending the upper part of the contact sleeve over theshoulder formed in the contact pin 21 by the conjunction of its constantdiameter tip portion 27 and its reverse-tapered portion 28. A positivelocking etfect is thus achieved.

It will be evident that in addition to its locking function the clampingplate 23 also provides protection for the contact members againstinadvertent damage, and particularly protects the thin-walled sleevecontacts 22 against damage when the two parts of the connector areseparated. Seals to prevent the ingress of moisture into the spacebetween the body members 12 and the clamping member 23 when the parts ofthe connector are engaged, are formed by walls 31 of part-circularcross-section. projecting from the face of each body member 12 andcompletely surrounding the contact area; these walls bear against theadjacent face of the clamping plate 23 to provide a seal. It will benoted that, except for its central boss. which receives the securingscrew 24, the face of the clamping plate 23 adjacent to the socket partof the connector is relieved to provide a clearance.

In many applications, it is necessary to provide a mechanical retainingdevice between the two halves of the connector in addition to thatprovided by the contact clamping means; for example safety regulationsfor a particular application may specify that a mechanical retainingdevice between the halves of the connector should be completelyindependent of the electrical connections. The connector shown in thedrawings is therefore provided with a bayonet-union type retainingdevice, shown in the general view which forms FIG. 5. A bayonet lockingsleeve 32 can revolve about the plug part of the connector, to which itis secured, its skirt projecting beyond the plug part 10 to receive thesocket part 11. Four axial slots 33, and corresponding circumferentialslots 34, leading out of them, co-operate with the heads of the studs(which lock the body retaining ring 14 of the socket part 11 to itscable sleeve 13) to lock the two parts of the connector together. Theaxis slots 33 in the locking sleeve extend beyond the correspondingcircumferential slots 34 for approximately half the length of the sleeveto receive four corresponding studs 35 projecting radially from thecircumference of the clamping plate 23, of which they form integralparts.

The angular motion of the locking sleeve 32 necessary to cause theco-operating studs 15 to pass from the axial slots 33 to their engagedpositions at the end of the circumferential slots 34 thus also moves theclamping plate 23 from its released to its clamped position. A singlemovement of the locking sleeve 32 thus mechanically locks the two partsof the connector together by virtue of the bayonet-union type retainingdevice it embodies, and also effects the individual clamping of eachco-opcrating contact pair of the connector through the medium of theclamping plate 23. The simultaneous release of the contacts and of thebayonet union is efiected in the same way.

On engagement of the two parts of the connector, the bayonet lockingsleeve 32, which is free to rotate on the plug part 10 of the connector,is placed over the socket part 11 with the clamping plate studs 35passing up its axial slots 33; the engagement of these slots with theco-operating studs 15 on further engagement of the parts ensures thatthe clamping plate 23 is in its released position before engagement ofthe contact pins and sleeves occurs. It will be seen from FIG. 2 that acompletely symmetrical disposition of the contacts is employed, correctlocation of the two body members 12 of the connector prior to engagementof the contact pins and sleeves being ensured by a pair of locating tabs36, of different sizes, extending from one connector part to entercorresponding recesses formed in the other part. Engagement of thecontact pins and sleeves presents no difficulty, since the clearanceafforded by the enlarged ends 25a of the locking slots in the clampingplate 23 permits slight movement of the contact sleeves to accommodatethe pins.

In a modified version of this connector, the composite construction ofthe two parts of the connector, involving the assembly of a number ofcomponent parts and also involving the use of such devices as moistureseals and cable anchorages, is abandoned in favour of a one piecemoulded construction for each part of the connector; each connector partthen comprising a solid block of moulded insulating material in whichthe plug or socket contact members are embedded together with theconductors connected to them. In a construction similar to that shown inthe drawings, for example, the clamping plate 23 and the bayonet lockingsleeve 32 would be the only removable parts of the connector.

Although the connector shown in the drawings is employed for connectingtogether the free ends of a pair of multi-core cables, it is evidentlyequally suitable for connecting such a cable to a piece of apparatus,one part of the connector being then provided with a flange forreceiving it to the apparatus.

FIG. 6 of the drawings shows a cross-section through the mating contactpairs of a further form of connector, in which a contact clamping plateis again arranged for limited movement in a direction normal to the axesof the co-operating contact pins and sleeves 81 to effect its clampingand unclamping action. In this version of the connector, however, theclamping plate 80 is arranged for limited rectilinear movement, being arectangular plate slidably mounted within a rectangular body member 82of one part of the connector. The pins and sleeves 81 are arranged inthree similar rows and the corresponding tapered slots 83 formed in theplate 80 for each contact pair communicate with each other to form threeirregular slots running along the length of the plate 80. The plate isslightly longer than the corresponding dimension of the body member 82,so that in either operative position it projects at one side of the bodymember.

As in the versions previously described, the clamping plate 80 may bearranged to co-operate with, or to form part of, a mechanical lockingmeans for the two parts of the connector.

What I claim as my invention and desire to secure by Letters Patent is:

1. An electrical connector comprising a first connector part having atleast one contact pin having a tip portion and a second portion ofreduced thickness compared with the tip portion, a second connector parthaving at least one corresponding hollow contact sleeve engaging overthe contact pin and being slotted and inwardly-deformable at least overthat portion engaging the reducedthickness portion of the pin, aclamping member formed with at least one slot having an enlarged portionof a dimension greater than the free dimension of the slotted portion ofsaid sleeve and a narrower portion of a dimension less than said freedimension, said clamping mem her being movable transversely of said pinand sleeve between a released position in which the inwardlydeformableportion of the sleeve co-operates with the enlarged portion of the slotand a clamped position in which the inwardly-deformable portion of thesleeve lies within the narrower portion of the slot thereby to bedeformed inwardly to grip the reduced-thickness portion of the pin.

2. An electrical connector as claimed in claim 1 comprising pivotalmounting means whereby the clamping member is pivotally mounted on oneconnector part for angular movement between its released and clamped"positions.

3. An electrical connector as claimed in claim 2 comprising a slottedlocking sleeve rotatably mounted on one connector part, projections onthe other connector part co-operating with said locking sleeve, and anoperative connection between the locking sleeve and the clamping member,at least when the connector parts are engaged, whereby rotation of thelocking sleeve rotates the clamping member between its released andclamped" positions.

4. An electrical connector comprising a first connector part having aplurality of aligned contact pins, each pin having a tip portion and asecond portion of reduced thickness compared with the tip portion, asecond connector part having a plurality of corresponding aligned hollowcontact sleeves each sleeve engaging over a contact pin and each sleevebeing slotted at least over that portion engaging the reduced-thicknessportion of the pin, a clamping member formed with a plurality of slots,each slot having an enlarged portion of a dimension greater than thefree dimension of the slotted portion of said sleeve and a narrowerportion of a dimension less than said free dimension, said clampingmember being movable transversely of said pins and sleeves between areleased position in which the slotted portion of the sleeve co-operateswith the enlarged portion of the slot and a clamped position in whichthe slotted portion of the sleevelies within the narrower portion of theslot thereby to be deformed inwardly to grip the reduced-thicknessportion of the pin.

5. An electrical connector as claimed in claim 4 comprising pivotalmounting means whereby the clamping member is pivotally mounted on oneconnector part for angular movement between its released and clampedpositions.

6. An electrical connector as claimed in claim 5 comprising a slottedlocking sleeve rotatably mounted on one connector part, projections onthe other connector part co-operating with said locking sleeve, and anoperative connection between the locking sleeve and the clamping member,at least when the connector parts are engaged, whereby rotation of thelocking sleeve rotates the clamping member between its released andclamped posi tions.

References Cited in the file of this patent UNITED STATES PATENTS

